Settlement, growth and survival of eastern oysters on alternative reef substrates

Restoration of the native eastern oyster (Crassostrea virginica) has been severely hindered by the dwindling supply and rising costs of fossil and new oyster shell for use in reef restoration. Consequently, emphasis has shifted to the use of alternative oyster reef materials, which need to be tested for their effectiveness as settlement substrate. Furthermore, low recruitment of wild larvae has also impeded restoration, indicating a need to assess the potential of field setting of cultured larvae. We experimentally examined oyster settlement, growth and survival on unconsolidated oyster shell, oyster shell embedded vertically in concrete, and concrete Oyster Castles® in field and mesocosm experiments. In addition, we examined settlement success of cultured larvae in the mesocosm experiment. In the field experiment, juvenile recruitment was 3x higher on castles and unconsolidated shell than on embedded shell. Castles retained 4x the number of oysters and hosted 5x the biomass than embedded shell, and retained 1.5x the oysters and hosted 3x the biomass than unconsolidated shell. The proportion of live oyster recruits on castles was 1.5x that on both embedded and unconsolidated shell. In the mesocosm experiment (90-d post-larval deployment), the castles recruited, retained, and hosted an oyster biomass 4x higher than that of unconsolidated and embedded shell. This study confirms that artificial reef materials such as Oyster Castles® are suitable alternative substrates for oyster restoration, and remote setting of larvae onto conditioned substrate can be effective under controlled environmental conditions. Future restoration efforts should consider use of alternative reef substrates and field setting of larvae to maximize oyster recruitment, while simultaneously minimizing the cost of reef restoration.

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Success of concrete and crab traps in facilitating Eastern oyster recruitment and reef development

PeerJ ◽

10.7717/peerj.6488 ◽

2019 ◽

Vol 7 ◽

pp. e6488

Author(s):

Emma E. Johnson ◽

Miles D. Medina ◽

Ada C. Bersoza Hernandez ◽

Gregory A. Kusel ◽

Audrey N. Batzer ◽

...

Keyword(s):

Low Cost ◽

Concrete Structures ◽

Oyster Shell ◽

Cost Effective ◽

Eastern Oyster ◽

Market Size ◽

Oyster Reefs ◽

Reef Development ◽

Reef Restoration ◽

Oyster Restoration

Background Abundance of the commercially and ecologically important Eastern oyster, Crassostrea virginica, has declined across the US Eastern and Gulf coasts in recent decades, spurring substantial efforts to restore oyster reefs. These efforts are widely constrained by the availability, cost, and suitability of substrates to support oyster settlement and reef establishment. In particular, oyster shell is often the preferred substrate but is relatively scarce and increasingly expensive. Thus, there is a need for alternative oyster restoration materials that are cost-effective, abundant, and durable. Methods We tested the viability of two low-cost substrates—concrete and recycled blue crab (Callinectes sapidus) traps—in facilitating oyster recovery in a replicated 22-month field experiment at historically productive but now degraded intertidal oyster grounds on northwestern Florida’s Nature Coast. Throughout the trial, we monitored areal oyster cover on each substrate; at the end of the trial, we measured the densities of oysters by size class (spat, juvenile, and market-size) and the biomass and volume of each reef. Results Oysters colonized the concrete structures more quickly than the crab traps, as evidenced by significantly higher oyster cover during the first year of the experiment. By the end of the experiment, the concrete structures hosted higher densities of spat and juveniles, while the density of market-size oysters was relatively low and similar between treatments. The open structure of the crab traps led to the development of larger-volume reefs, while oyster biomass per unit area was similar between treatments. In addition, substrates positioned at lower elevations (relative to mean sea level) supported higher oyster abundance, size, and biomass than those less frequently inundated at higher elevations. Discussion Together, these findings indicate that both concrete and crab traps are viable substrates for oyster reef restoration, especially when placed at lower intertidal elevations conducive to oyster settlement and reef development.

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PREFERENSI PENEMPELAN, PERTUMBUHAN, DAN SINTASAN LARVA TERIPANG PASIR, Holothuria scabra PADA SUBSTRAT LAMUN YANG BERBEDA

Jurnal Riset Akuakultur ◽

10.15578/jra.11.3.2016.249-258 ◽

2017 ◽

Vol 11 (3) ◽

pp. 249

Author(s):

Lisa Fajar Indriana ◽

Yuli Afrianti ◽

Sitti Hilyana ◽

Muhammad Firdaus Firdaus

Keyword(s):

Survival Rate ◽

Economic Value ◽

Growth And Survival ◽

Holothuria Scabra ◽

Enhalus Acoroides ◽

Randomized Design ◽

Settlement Substrate ◽

Cymodocea Rotundata ◽

Syringodium Isoetifolium ◽

Cymodocea Serrulata

Teripang pasir, Holothuria scabra merupakan komoditas hasil laut yang bernilai ekonomis tinggi. Penangkapan berlebihan stok di alam mendorong berkembangnya kegiatan budidaya. Penempelan merupakan fase kritis pada larva teripang karena terjadi peralihan sifat planktonis ke bentik yang memerlukan substrat. Penelitian ini bertujuan untuk mengetahui preferensi penempelan, pertumbuhan, dan sintasan larva H. scabra fase penempelan pada substrat lamun yang berbeda. Penelitian menggunakan metode rancangan acak lengkap dengan perlakuan empat jenis daun lamun berbeda dan lima ulangan. Perlakuan terdiri atas Enhalus acoroides (L-1), Syringodium isoetifolium (L-2), Cymodocea serrulata (L-3), dan Cymodocea rotundata (L-4). Jumlah awal larva sebanyak 1.000 individu dan substrat dirangkai dengan luasan yang sama sebesar 12 cm x 17 cm untuk setiap unit penelitian. Hasil penelitian menunjukkan jenis lamun yang digunakan sebagai substrat berpengaruh secara nyata terhadap preferensi penempelan dan sintasan larva teripang pasir, namun tidak berpengaruh terhadap pertumbuhan. E. acoroides menunjukkan hasil terbaik dengan preferensi penempelan 0,26 ind. cm-2 dan sintasan 10,66%; sehingga layak digunakan sebagai substrat penempelan dalam pembenihan teripang pasir, H. scabra.Holothuria scabra larvae on different seagrass substrates. By: Lisa Fajar Indriana, Yuli Afrianti, Sitti Hilyana, and Muhammad FirdausSandfish Holothuria scabra is marine commodities with a high economic value. Overfishing of natural stocks has compelled an interest to begin aquaculture practice. Settlement is a critical phase for the planktonic larvae as they will transform to benthic form in the presence of substrate. This study aims to evaluate the settlement preferences, growth, and survival rate of H. scabra larvae settled on different seagrass leaves. The research was conducted using the Completely randomized design with four different species of seagrass leaves and five replications. The treatments consist of Enhalus acoroides (L-1), Syringodium isoetifolium (L-2), Cymodocea serrulata (L-3), and Cymodocea rotundata (L-4). Initial number of larvae was 1,000 individuals and the substrate was set with same widthof 12 cm x 17 cm for each unit. Results of the experiment indicated that settlement preference and survival rate of H. scabra larvae was significantly affected by seagrass used as substrate while no significantly differences was observed for growth of larvae. E. acoroides showed the best result with 0.26 ind. cm-2 settelement preference and 10.66% survival rate, so that suitable to be used as settlement substrate in H. scabra hatchery.

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The potential effects of pre-settlement processes on post-settlement growth and survival of juvenile northern rock sole (Lepidopsetta polyxystra) in Gulf of Alaska nursery habitats

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2017.02.028 ◽

2017 ◽

Vol 189 ◽

pp. 46-57 ◽

Cited By ~ 2

Author(s):

Erin J. Fedewa ◽

Jessica A. Miller ◽

Thomas P. Hurst ◽

Duo Jiang

Keyword(s):

Gulf Of Alaska ◽

Growth And Survival ◽

Nursery Habitats ◽

Settlement Growth

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Growth and survival of Pocillopora damicornis (Scleractinia: Pocilloporidae) coral fragments and their potential for coral reef restoration in the Tropical Eastern Pacific

Marine Biology Research ◽

10.1080/17451000.2018.1528011 ◽

2018 ◽

Vol 14 (8) ◽

pp. 887-897 ◽

Cited By ~ 5

Author(s):

Luis David Lizcano-Sandoval ◽

Edgardo Londoño-Cruz ◽

Fernando A. Zapata

Keyword(s):

Coral Reef ◽

Eastern Pacific ◽

Pocillopora Damicornis ◽

Tropical Eastern Pacific ◽

Growth And Survival ◽

Reef Restoration

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Settlement, Growth, and Survival of Eastern Oysters on Alternative Reef Substrates

Journal of Shellfish Research ◽

10.2983/035.034.0205 ◽

2015 ◽

Vol 34 (2) ◽

pp. 241-250 ◽

Cited By ~ 18

Author(s):

Seth J. Theuerkauf ◽

Russell P. Burke ◽

Romuald N. Lipcius

Keyword(s):

Growth And Survival ◽

Eastern Oysters ◽

Settlement Growth

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Coral farming: effects of light, water motion and artificial foods

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315411001500 ◽

2011 ◽

Vol 92 (4) ◽

pp. 721-729 ◽

Cited By ~ 9

Author(s):

Zac H. Forsman ◽

Bethany K. Kimokeo ◽

Christopher E. Bird ◽

Cynthia L. Hunter ◽

Robert J. Toonen

Keyword(s):

Low Cost ◽

Optimal Growth ◽

Growth Conditions ◽

Low Flow ◽

Constant Flow ◽

Pocillopora Damicornis ◽

Growth And Survival ◽

Light Water ◽

Reef Restoration ◽

Water Motion

Improved coral cultivation will facilitate the reduction of wild harvesting, reef restoration, preservation of biodiversity, and the use of corals as model experimental organisms. In this study, we examine species-specific responses in growth and survival of corals from the effects of light, water motion and artificial (i.e. non-living aquarium trade) food supplements. Three species representing distinct, diverse and abundant coral genera were chosen (Montipora capitata(Mc), Porites compressa (Pc) and Pocillopora damicornis (Pd)) for three experiments to examine: (1) the interaction of water flow and light on growth and survival of Mc and Pc; (2) the effects of artificial foods on Mc, Pc and Pd; and (3) the effects of increasing dosage of artificial foods in an open system on Mc and Pc. Pc thrived at the highest light levels with low flow, while Mc exhibited bleaching and reduced growth in the same conditions and grew best in shaded treatments. High constant flow (~11 cm s-1) resulted in slightly less overall growth than low constant flow (~4 cm s-1). Some artificial foods resulted in a significant increase in growth in Mc and Pd, but not in Pc. These combined results suggest that Mc may be more heterotrophic than Pc. This study illustrates that each species has unique requirements for optimal growth conditions that can be determined by relatively simple and low cost experiments, but that ideal conditions for one species might not be generalized to others.

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Measuring kiwifruit resistance to armoured scale insect pests

New Zealand Plant Protection ◽

10.30843/nzpp.2012.65.5400 ◽

2012 ◽

Vol 65 ◽

pp. 290-290

Author(s):

M.G. Hill ◽

N.A. Mauchline ◽

K.A. Stannard

Keyword(s):

Insect Pests ◽

Important Determinant ◽

Scale Insect ◽

Growth And Survival ◽

Relative Susceptibility ◽

Defensive Responses ◽

Laboratory Cultures ◽

Settlement Growth

A bioassay for assessing relative susceptibility of kiwifruit germplasm to latania scale (Hemiberlesia lataniae) has been developed and validated The method uses cut canes collected from dormant kiwifruit vines in winter Canes are held in coolstore (0C) until required Lengths of cane (40 cm) are held with one end in water at 20C and scale insect crawlers from laboratory cultures are encouraged to settle beneath wool wrapped around the cane Percentage crawler settlement numbers of insects surviving to adulthood and their size are determined and used to assess the relative susceptibility of the plant This method has been validated for H lataniae and used to study kiwifruit resistance and defensive responses The bioassay did not work satisfactorily for greedy scale (H rapax) as crawler settlement was very low Further research has identified cane age as an important determinant of H rapax crawler settlement Young canes harvested in summer enable good settlement of H rapax but canes of this age do not last long enough for the insects to mature (1012 weeks) Canes harvested in autumn while still green will survive to support H rapax settlement growth and survival and can be used to compare kiwifruit resistance to both scale species

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